This invention relates to an improved variable resistance exercise machine adapted to perform multiple exercises that accommodate the musculoskeletal makeup of a person.
Many persons utilize weight training to develop strength, to enhance their personal appearance, or for rehabilitation. Weight training can be accomplished through the use of weight machines and/or free weights, i.e., dumbbells, barbells, and weighted plates. Both types of weight training have advantages and disadvantages.
Free weights are generally more inexpensive and more versatile than weight or exercise machines. One set of free weights can be used to work many different muscle groups. Free weights also offer an improved range of motion over exercise machines, which are restricted to one plane of movement. The primary disadvantage of free weights is safety. Because free weights are not restricted in their range of motion, an exerciser could drop a weight on him/herself, the bar could fall on an exerciser when weighted plates are being added or removed, or an exerciser could be trapped underneath a weighted bar. Because of these safety risks, most exercisers have to work out in pairs or specialized facilities to protect themselves. This also limits the exerciser to times and places where they can work out.
Because of these disadvantages relating to free weights, exercise machines have become more common. These machines offer improved safety because the weights are usually restricted to one plane of motion. This prevents a weight from falling on an exerciser. Further, this restricted range of motion only allows a bar to return to an initial starting position, which prevents an exerciser from being pinned underneath a bar. Exercise machines also improve safety because the machine""s frame prevents any imbalance during the addition or removal of weights. In fact, some machines come with all of the weights already equipped on the machine such that the weight can be changed by moving a pin.
Although exercise machines offer improved safety over free weights, they also have disadvantages. The primary disadvantage of exercise machines is that they are usually designed to provide only one exercise. For the machines that provide more than one exercise, the cost usually increases proportionately with the additional exercises offered by a single machine. Thus, it is very expensive to own machines that allow exercise of different muscle groups, especially for individual owners.
The prior art has countless disclosures relating to exercise machines or apparatuses designed for improving the muscle characteristics of differing muscle groups. Most of these machines use cables, pulleys or levers to carry a weight over a restricted range of motion. For example, U.S. Pat. No. 5,135,449 discloses a rowing exercise machine. This machine uses a pair of levers to provide the resistance to an exerciser. This machine is only suited to provide one exercise. Another example, U.S. Pat. No. 5,184,991, discloses a multi-station exercise machine for exercising different muscle groups, which uses pulleys and levers. It should be noted that this apparatus requires the exerciser to move to different locations on the apparatus to carry out the different exercises. Accordingly, a major problem of exercise machines is to provide a variety of exercises in a compact machine that can be performed from substantially the same location on the machine.
Many exercise machines are also difficult and costly to build. Many machines use a series of levers, pulleys, cables, or other specialized components. These specialized components increase the complexity of the design and the time to assemble the machines. Moreover, the cost to build and replace these parts is relatively high when compared with machines that do not require these components. Thus, machines that use specialized components are more difficult to manufacture and maintain and are more expensive than other exercise machines.
Another problem is that free weights and some exercise machines on the market today are not designed to provide a variable resistance workout to the exerciser. By variable resistance I mean a change in the force that is needed to move a given (predetermined) weight over a range of motion. The advantage of using variable resistance in weight training is that it allows for a more efficient workout by causing muscle groups to work hardest at a specified range of motion. Variable resistance also helps to prevent injury by allowing an exerciser to exert less force at vulnerable points in a range of motion during an exercise. For example, when conducting a squat, the exerciser is at risk of back injury when first picking up a weight from the lowest position. Variable resistance would allow the exerciser to initially lift the weight with less force at this vulnerable position. Then, as the exerciser continues on the range of motion in the squat, the force necessary to move the weight would increase. By using variable resistance during a work out, an exerciser can better isolate specific muscle groups and avoid injury to others. Most exercises that utilize free weights and exercise machines do not provide variable resistance. Instead the force that an exerciser must exert is substantially constant over the entire range of motion.
An object of the invention, therefore, is to provide a variable resistance exercise machine.
Another object of the invention is to provide a safe exercise machine that has a restricted range of motion and allows an exerciser to work out without the aid from others.
It is a further object of the invention to provide an exercise machine that provides a variety of exercises that can be substantially carried out from one location on the machine.
Another object of the machine is to allow an exerciser to work out in less space.
A further object of the invention is to provide a machine that is more easily manufactured and assembled.
Still a further object of the invention is to provide an exercise machine that provides a variety of exercises that is less costly to manufacture and more affordable to the exerciser.
It is a further object of this invention to provide an exercise machine wherein some or all of the above-mentioned advantages are realized.
These and other objects and advantages of the invention will be apparent to those skilled in the art upon reading the following detailed description and upon reference to the drawings.
The subject invention contemplates a variable resistance exercise machine having a support frame, a rotatable shaft, a pair of weight arms, a work arm, and at least one weight arm support. The shaft is horizontally mounted in a fixed, predetermined position on the support frame for rotation about its longitudinal axis. The pair of weight arms are connected to and extend from the shaft at opposite ends thereof in a direction substantially perpendicular to the longitudinal axis of the shaft. Each of the weight arms has a weight hub for carrying at least one weight at a point distant from their respective connections to the rotating shaft.
The work arm is connected to and extends from the shaft at a point intermediate of and spaced from the connections between the weight arms and the shaft. The work arm is adapted to be actuated by an exerciser, whereby the weights are moved in arcuate paths relative to the longitudinal axis of the shaft from respective first positions to second positions. Thereby, the resistance to rotation provided by the weight arms also varies as the weight arms travel in an arcuate direction.
The weight arm support selectively supports at least one of the weight arms in a substantially non-vertical position. It prevents rotation of the shaft in a direction such that the supported weight arm would become oriented in a substantially downward, vertical position and permits free rotation of the shaft in a second direction away from the support.
In preferred aspects, the sides of the frame of the machine are substantially U-shaped, with a first half equipped for mounting an adjustable and removable seat, and a second half open for performing exercises which require the exerciser to stand, such as squats and dead lifts. The second half is also adapted to support the rotating shaft, preferably mounted by pillow block bearings. Thus, the seat is supported by the frame behind the shaft. When an exerciser is seated on the machine, he will usually be facing the rotating shaft. However, the seat can be removed to provide space for other exercises, such as leg press.
The work arm can be releasably connected to the shaft via adjustable receivers, and may take many forms so as to facilitate different types of exercises. For example, the work arm can be adapted to perform at least the following exercises: lat pull down, military press, chest press, tricep extension, seated dips, bicep curl, low row, lying leg press, squats, dead lifts, abdominal crunches, leg extension, seated leg curl, lat pull over, etc. The weight arm can be adapted to hold at least one removable weight, usually in the form of a plate, such as would be added to a free weight bar. The frame will provide the support necessary to balance the machine, specifically the rotating shaft, to keep the weights and shaft in place.
In accordance with the objects of the invention, when an exerciser is seated facing the shaft, the work arm can be actuated from this single position so that the exerciser can perform different exercises which require either pushing the work arm away from the exerciser, or pulling to work arm toward the exerciser. Thus, the work arm can be actuated by an exerciser causing the shaft to rotate in a clockwise or a counter-clockwise direction. This feature, in addition with the interchangeable work arms, allows the machine to provide many different exercises with the exerciser at substantially the same location on the machine.
Further, because the exerciser""s range of motion is restricted, the machine provides increased safety and allows an exerciser to work out alone.
Further, because the machine does not require pulleys, or cables, the machine is relatively inexpensive to manufacture and assembly is easy and efficient. Thus, the machine provides a variety of exercises at decreased cost to the exerciser.
The exercise machines function as follows: as the exerciser pushes or pulls the work arm, the shaft will rotate, causing the weight arm to travel in an arcuate direction from a starting or first position to a second position. As the weight arm moves in an arcuate direction, the resistance to rotation by the weight arm varies. The starting resistance is that resistance that the exerciser feels when the exerciser first begins to pull or push the work arms. When the weight arm has a substantially vertical starting position, the starting resistance provided by the weight arm is substantially zero. Then, as an exerciser pulls the work arms, the weight arms will travel to a second position counterclockwise of the starting position. At this substantially vertical starting or first position, the resistance to the exerciser is virtually zero. As the exerciser pulls the work arm toward themselves, the weight arm gains increased resistance as it approaches a substantially horizontal position in the counterclockwise direction. The force required to actuate the work arm also increases over this range of motion. Then, as the weight arm travels from this substantially horizontal position to a substantially vertical position, the resistance decreases. Thus, the resistance to the exerciser varies as the weight arm is carried along its arcuate path. Alternatively, the second position can be clockwise of the starting or first position.
The machine has a means for supporting the weight arms in one or more substantially non-vertical positions to adjust the starting resistance provided by the weight arm. Thus, the weight arm can have a substantially non-vertical starting position, whereby the starting resistance provided by the weight arm is greater than zero. Also, the first position of the weight arm may be selected to adjust the starting resistance provided by the weight arm. Thus, in accordance with the objects of the invention, the exercise machine provides variable resistance to the exerciser.
These and other features of the invention will be more readily understood in view of the following detailed description and drawings.